There are serious demands in the home and office furniture industry for a strong and inexpensive hinge for swinging doors which can be easily installed in a concealed configuration. Such hinges should be usable with the swinging doors disposed flush to one or both side faces of the door frame, which swings open in either of two opposite directions. Such hinges should not be visible once they are installed whether the swinging door is fully closed, or fully open or partially open. At the present time, there is no such hinge that has all of the aforementioned features.
The primary object of the present invention is to provide a hinge for swinging doors that enables them to fit a single or a pair of swinging doors flush to one or both side faces of the door frame wherein the swinging doors can be swung open in either of two directions.
Another object of the present invention is to provide the door hinges disposed at the coners of the swinging door wherein the door hinges are concealed for all instances no matter if either the swinging doors are fully closed or fully or partially open.
A further object of the present invention is to provide a door hinge with a spring bias means that automatically retains the swinging door at the fully closed position.
Still another object of the present invention is to provide a door hinge wherein the hinge pin rigidly affixed to the first swinging half of the door hinge engages rotatably and shiftably a slotted hole disposed in the second swinging half of the hinge.
Still a further object of the present invention is to provide a door hinge including a spring bias means that retains the hinge pin at one extremity of the slotted hole rotatably and shiftably engaged by the hinge pin.
Yet another object of the present invention is to provide a door hinge made essentially of a sheet metals and metal wires or rods.
Yet a further object of the present invention is to provide a door hinge with the hinge pin rotatably and shiftably engaging a hole of a substantially triangular cross section wherein spring bias means retain the hinge pin at one of three corners in said hole when an external counter-acting force is absent.
These and other objects of the present invention will become clear as the description thereof proceeds.